My FAVORITE sites for printable coupons are:
coupons.com
redplum.com
smartsource.com
If you sign up for:
P&G - you get e-mails for free product samples and/or coupons they are sending out.
Free Coupon Alerts - you get an e-mail when new printable coupons come out.
I will be adding to this page as time goes on so check back often!!!